Communicator, electric working machine, and communication method

ABSTRACT

A communicator in one aspect of the present disclosure includes a connector, a communication circuit, and a communication controller. The connector is electrically coupled to an electric working machine. The communication circuit performs wireless communication. The communication controller cyclically transmits operational information without specifying a recipient via the communication circuit in response to an operating mode of the communication controller being set to an operation-transmission mode. The operational information indicates an operating state of the electric working machine.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a Continuation of Application No. 16/006,338 filed Jun. 12,2018, which claims the benefit of Japanese Patent Application No.2017-118753 filed Jun. 16, 2017 in the Japan Patent Office, thedisclosure of which is incorporated herein by reference.

BACKGROUND

The present disclosure relates to a wireless communication technique foran electric working machine.

EP 2628431 discloses a technique to equip a machine tool and a dustcollector with a communication tool and operate the machine tool inconjunction with the dust collector through communication between theirown communication tools.

SUMMARY

When different electric working machines communicate with each otherthrough their own communication tools, such communication is generallyconducted on one-on-one basis only between a first electric workingmachine and a second electric working machine. In other words, the firstelectric working machine generally specifies the second electric workingmachine and communicates with the second electric working machine toachieve the conjunctive operation with the second electric workingmachine.

Nevertheless, the first electric working machine that is designed forconjunctive operation with only the second electric working machine isnot always useful for a user. For example, the user may also preferoperating two or more additional electric working machines inconjunction with the first electric working machine in addition to thesecond electric working machine.

Preferably, one aspect of the present disclosure can improve usefulnessof an electric working machine.

A communicator in one aspect of the present disclosure includes aconnector, a communication circuit, and a communication controller. Theconnector is configured to be electrically coupled to a transmissionside electric working machine. The communication circuit is configuredto perform wireless communication. The communication controller isconfigured such that its operating mode is settable to anoperation-transmission mode in response to the connector being coupledto the transmission side electric working machine. The communicationcontroller is further configured to cyclically transmit operationalinformation via the communication circuit without specifying a recipientin response to the operating mode being set to theoperation-transmission mode. The operational information indicates anoperational state of the transmission side electric working machine.

Such a communicator configured as above easily allows an unspecifiedelectric working machine, which is configured to receive the operationalinformation, to operate in conjunction with the transmission sideelectric working machine coupled to the communicator in accordance withthe operational information. This helps to improve usefulness of thetransmission side electric working machine.

The operational information may indicate a driving state of a tool ofthe transmission side electric working machine.

The communicator may also include a manipulator configured to bemanipulated by a user of the communicator. The communication controllermay also be configured to change the operating mode in response to amanipulation performed on the manipulator. This configuration enablesthe user to easily change the operating mode.

The communication controller may be further configured to cyclicallytransmit different information corresponding to the operating mode ofthe communication controller via the communication circuit. Such acommunicator can transmit various information in accordance with theoperating mode if specific information is appropriately allocated foreach operation mode. In addition to the operation-transmission mode, thecommunication controller may also include, for example, an operatingmode that does not involve a transmission of the operationalinformation. In this case, the user can easily select whether to operatethe unspecified electric working machine in conjunction with thetransmission side electric working machine.

The communicator may also include a display that is configured to showinformation. The communication controller may also be configured to showmode information on the display. The mode information may includeinformation to identify whether the operating mode is set to theoperation-transmission mode.

The communicator configured as above enables the user to easilyrecognize whether the operating mode is set to theoperation-transmission mode, in other words, whether the operating modeis set to a mode in which the operational information is transmitted.

The communication controller may be further configured to cyclicallytransmit the operational information at a first transmission cycle inresponse to the operating mode being set to the operation-transmissionmode. The communication controller may be further configured tocyclically transmit a given information at a second transmission cycle,different from the first transmission cycle, in response to theoperating mode being set to a given transmission mode, different fromthe operation-transmission mode. This configuration enables thecommunicator to set an appropriate transmission cycle in accordance withthe operating mode, which can reduce electric power consumed for thetransmission of information.

The first transmission cycle may be shorter than the second transmissioncycle. In the operation-transmission mode, changes in the operationalinformation can be promptly notified by a transmission at the firsttransmission cycle that is shorter than the second transmission cycle.

The communication controller may also be configured to cyclicallytransmit registration information via the communication circuit inresponse to the operating mode being set to a registration-transmissionmode. The registration information may include a command directed to afirst additional communicator to conduct a registration of firstcommunicator information that identifies the communicator.

This configuration enables the communicator to register the firstcommunicator information in the first additional communicator inresponse to the operating mode being set to theregistration-transmission mode. For example, by transmitting the firstcommunicator information in addition to the operational information, thetransmitted operational information can be effective only to the firstadditional communicator.

The communication controller may also be configured to cyclicallytransmit deletion information via the communication circuit in responseto the operating mode being set to a deletion-transmission mode. Thedeletion information may include a command directed to the firstadditional communicator to delete the registration of the firstcommunicator information.

This configuration enables the communicator to cause the firstadditional communicator to delete the registration of the firstcommunicator information in response to the operating mode being set tothe deletion-transmission mode.

The connector may also be configured to be electrically coupled to areceiving side electric working machine. The communication controllermay also be configured such that the operating mode is settable to anoperation-receiving mode in response to the connector being coupled tothe receiving side electric working machine. The communicationcontroller may also be configured to cyclically monitor, at a firstmonitoring cycle, whether the operational information is received viathe communication circuit in response to the operating mode being set tothe operation-receiving mode. The communication controller in theoperation-receiving mode may be further configured to output theoperational information received.

This configuration enables the communicator to output to the receivingside electric working machine the operational information received inresponse to the operating mode being set to the operation-receivingmode. As a result, the receiving side electric working machine canoperate in conjunction with the transmission side electric workingmachine.

The operational information may also indicate a driving state of a toolof the transmission side electric working machine.

The communication controller may also be configured to cyclicallymonitor, at a second monitoring cycle, information received via thecommunication circuit in response to the operating mode being set to await-receiving mode. The communication controller in the wait-receivingmode may further be configured to change the operating mode to theoperation-receiving mode in response to a reception of the operationalinformation via the communication circuit.

This configuration enables the communicator to operate, for example, inthe wait-receiving mode under normal conditions and operate in theoperation-receiving mode in response to a reception of the operationalinformation. In other words, the communicator can operate in anappropriate mode depending on whether the operational information isreceived.

The first monitoring cycle may be shorter than the second monitoringcycle. This configuration enables the communicator to immediatelyrecognize changes in the operational information received.

The operational information may be transmitted from a second additionalcommunicator. The second additional communicator may be configured totransmit second communicator information that identifies the secondadditional communicator. The communication controller may also beconfigured to conduct a registration of the second communicatorinformation received via the communication circuit in response to theoperating mode being set to a registration-receiving mode. In addition,the communication controller may also be configured to change theoperating mode from the wait-receiving mode to the operation-receivingmode in response to a reception of the operational information and thesecond communicator information, registered in the communicationcontroller, via the communication circuit.

This configuration enables the communicator to easily register thesecond communicator information. In response to a reception of theoperational information corresponding to the registered secondcommunicator information, the communicator can effectively process thereceived operational information.

The communication controller may also be configured to delete theregistration of the second communicator information based on givendeletion information received via the communication circuit in responseto the operating mode being set to a deletion-receiving mode. Thisconfiguration enables the communicator to easily delete the registeredsecond communicator information. In other words, the communicator canregister and delete the second communicator information as necessary.

The communicator may also include a display that is configured to showinformation. The communication controller may further be configured toshow driving information on the display based on the operationalinformation received via the communication circuit. The drivinginformation may include information to identify whether the tool isdriven. This configuration enables the user to easily identify a drivingstate of the tool of the transmission side electric working machine.

Another aspect of the present disclosure is a transmission side electricworking machine that includes the aforementioned communicator and atransmission side driving device. The transmission side driving deviceis configured to drive a tool of the transmission side electric workingmachine.

Such a transmission side driving device configured as mentioned abovecan easily cause an unspecified other electric working machine, which isconfigured to receive operational information, to operate in conjunctionwith the transmission side electric working machine by transmitting theoperational information. The usefulness of the transmission sideelectric working machine can therefore be improved.

Yet another aspect of the present disclosure is a receiving sideelectric working machine that includes any one of the aforementionedcommunicators, and a receiving side driving device. The receiving sidedriving device is configured to drive a tool of the receiving sideelectric working machine.

This configuration enables the receiving side electric working machineto drive the tool of the receiving side electric working machine inaccordance with the driving state of the tool of the transmission sideelectric working machine in response to the operating mode of thecommunication controller of the communicator coupled to the receivingside electric working machine being set to the operation-receiving mode.The usefulness of the receiving side electric working machine cantherefore be improved.

Still another aspect of the present disclosure is a communicationmethod. The method may include setting an operating mode of acommunicator to an operation-transmission mode in response to thecommunicator being coupled to an electric working machine. The methodmay include cyclically transmitting operational information from thecommunicator without specifying a recipient in response to the operatingmode being set to the operation-transmission mode. The operationalinformation indicates an operational state of the electric workingmachine.

BRIEF DESCRIPTION OF THE DRAWINGS

An example embodiment of the present disclosure will be describedhereinafter with reference to the accompanying drawings, in which:

FIG. 1 is an explanatory diagram showing an outline of a communicationsystem;

FIG. 2 is an explanatory diagram showing an electrical configuration ofan electric power tool and a first communication device;

FIG. 3 is an explanatory diagram showing an electrical configuration ofa dust collector and a second communication device;

FIG. 4 is an explanatory diagram showing a configuration of a displayand display patterns;

FIG. 5 is an explanatory diagram showing an example operation of atransmission-oriented unit;

FIG. 6 is an explanatory diagram showing an example operation of asearch-oriented unit;

FIG. 7A is a flowchart showing a part of a communication controlprocess; and

FIG. 7B is a flowchart showing the rest of the communication controlprocess.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 1. Embodiment

(1-1) Outline of Communication System

A communication system shown in FIG. 1 includes a first electric workingmachine 1, a second electric working machine 50, and a mobile device100. In the present embodiment, the first electric working machine 1 maybe an electric power tool. In the explanation hereinafter, the firstelectric working machine 1 will be also called an electric power tool 1.The second electric working machine 50 may be a dust collector in thepresent embodiment. In the explanation hereinafter, the second electricworking machine 50 will be also called a dust collector 50.

The electric power tool 1 is, for example, a circular saw including acircular saw blade 20 (not shown in FIG. 1; see FIG. 2). It is merely anexample that the first electric working machine 1 is a circular saw; thefirst electric working machine 1 may be other electric power tool andmay therefore be other electric working machine.

The dust collector 50 includes, for example, a fan 60 (not shown in FIG.1; see FIG. 3). The dust collector 50 is configured to vacuum wasteparticles and dusts in its surrounding area by driving the fan 60. Inthe present embodiment, the dust collector 50 can vacuum powdery wasteand cutting scraps that are produced during the operation of theelectric power tool 1.

The electric power tool 1 is configured such that a first communicatingunit 30A is attachable to and detachable from the electric power tool 1.The dust collector 50 is configured such that a second communicatingunit 30B is attachable to and detachable from the dust collector 50.FIG. 1 shows the first communicating unit 30A and the secondcommunicating unit 30B attached to the electric power tool 1 and thedust collector 50 respectively. The first communicating unit 30A canwirelessly transmit and receive data. The second communicating unit 30Bcan also wirelessly transmit and receive data.

The first communicating unit 30A and the second communicating unit 30Bwirelessly communicate with each other to cause the dust collector 50 tooperate in conjunction with the electric power tool 1. To be morespecific, the first communicating unit 30A transmits information thatthe electric power tool 1 is in operation during the operation of theelectric power tool 1; the second communicating unit 30B receives thisinformation and transmits the information to the dust collector 50 andcauses the dust collector 50 to operate in conjunction with the electricpower tool 1.

The first communicating unit 30A and the second communicating unit 30Bare both configured to enable wireless communication by a predefinedtelecommunication system. The predefined telecommunication system in thepresent embodiment is in conformity with, for example, Bluetooth LowEnergy (hereinafter also called “BLE”) telecommunications standard.“Bluetooth” is a registered trademark.

The mobile device 100 is a data processing device with a wirelesscommunication function, such as a smartphone, a tablet, and a laptopcomputer. The mobile device 100 is also enabled to wirelesslycommunicate with the first communicating unit 30A and the secondcommunicating unit 30B through the aforementioned telecommunicationsystem.

(1-2) Electrical Configuration of Electric Power Tool and FirstCommunicating Unit

An electrical configuration of the electric power tool 1 and the firstcommunicating unit 30A will be explained next with reference to FIG. 2.The electric power tool 1 includes a tool main body 10, and a batterypack 25. The battery pack 25 is attachable to and detachable from thetool main body 10. FIG. 2 shows the tool main body 10 with the batterypack 25 and the first communicating unit 30A attached to the tool mainbody 10.

The battery pack 25 includes a battery 26 that is repeatedlyrechargeable. The battery 26 in the present embodiment is, for example,a lithium ion rechargeable battery. Nevertheless, the battery 26 may beany rechargeable battery other than the lithium ion rechargeablebattery. The battery pack 25 is configured to be attached to a not-showncharger to charge the battery 26.

The battery 26 may be included inside the tool main body 10. The battery26 is merely an example power source of the electric power tool 1. Theelectric power tool 1 may be enabled for operation by a power supplyfrom any power source other than the battery 26. For example, theelectric power tool 1 may be enabled for operation by receivingalternating-current (AC) power via a power-supply cord plugged into anoutlet of an AC power source, such as a commercial power source.

The tool main body 10 includes a motor 11, a main controller 12, apower-supply 13, a trigger switch 14, a role-determiner 15, a connector16, and the aforementioned saw blade 20. The trigger switch 14 is atrigger-type manipulation switch. The trigger switch 14 is turned on andoff by user manipulation.

The connector 16 includes a power-source terminal 16 a, a groundterminal 16 b, a role-determination terminal 16 c, and anoperational-signal terminal 16 d.

The power-source terminal 16 a is coupled to an output terminal of afirst power supply voltage Vc1 in the power-supply 13. The groundterminal 16 b is coupled to a ground line. The role-determinationterminal 16 c is coupled to the role-determiner 15. Theoperational-signal terminal 16 d is coupled to the main controller 12.

Electric power of the battery 26 (hereinafter also called “batterypower”) is delivered to the main controller 12 and the power-supply 13.Based on the delivered battery power, the power-supply 13 generates apower supply voltage that is lower than a voltage of the battery 26. Inthe present embodiment, the power-supply 13 generates the first powersupply voltage Vc1 and a second power supply voltage Vc2. A value of thefirst power supply voltage Vc1 may be 5 volts, for example. A value ofthe second power supply voltage Vc2 may be 3.3 volts, for example.

The first power supply voltage Vc1 and the second power supply voltageVc2 are used as power-supply power for operating each component in thetool main body 10. The first power supply voltage Vc1 can be suppliedfrom the power-source terminal 16 a to an outer subject.

The main controller 12 includes a microcomputer that includes a CPU 21,and a memory 22. The memory 22 may include a semiconductor memory suchas a RAM, a ROM, and a flash memory. The memory 22 stores variousprograms and data that the CPU 21 reads out and executes to achievevarious functions of the electric power tool 1.

These various functions may be achieved partially or entirely by ahardware that includes a combination of circuits, such as a logiccircuit and an analog circuit, and does not have to be achieved only bya software process as mentioned above.

In response to turning on of the trigger switch 14, the main controller12 supplies the motor 11 with the battery power to drive the motor 11 inaccordance with how the trigger switch 14 is manipulated. Driving of themotor 11 causes the saw blade 20 to rotate and enables the saw blade 20to work. In response to turning off of the trigger switch 14, the maincontroller 12 stops delivering the battery power to the motor 11 to stopthe motor 11, which leads the saw blade 20 to stop rotating.

The main controller 12 is basically configured to drive or stop themotor 11 in accordance with how the trigger switch 14 is manipulated.Nevertheless, the main controller 12 may be configured to stop the motor11 when the trigger switch 14 is turned on. For example, the batterypack 25 may be configured to transmit a signal to stop discharging tothe tool main body 10 in an occasion where a given condition to stopdischarging is satisfied during a discharge from the battery 26. Themain controller 12 may be configured to stop the motor 11 in response toreceiving the signal to stop discharging from the battery pack 25regardless of the trigger switch 14 being turned on.

The main controller 12 transmits an operation-state signal to theoperational-signal terminal 16 d during driving the motor 11. The maincontroller 12 may also transmits the driving-state signal when the driveof the motor 11 is resumed from a stop state. The main controller 12 mayalso transmits the driving-state signal continuously or intermittentlyduring the motor 11 being driven.

The main controller 12 transmits a stop-state signal to theoperational-signal terminal 16 d when the drive of the motor 11 isstopped. In a case where the main controller 12 is configured totransmit the driving-state signal continuously or intermittently duringthe motor 11 being driven, an end to the transmission of thedriving-state signal may correspond to a transmission of the stop-statesignal. The main controller 12 may also be configured to transmit thestop-state signal continuously or intermittently during the motor 11being stopped. The motor 11 may be any type of motor. The motor 11 maybe a brushed direct current (DC) motor, a brushless DC motor, or anothertype of motor.

The role-determiner 15 transmits a role-determining information to thefirst communicating unit 30A. The role-determining information is fordetermining how the first communicating unit 30A should operate. In thepresent embodiment, the role-determiner 15 transmits the second powersupply voltage Vc2, as the role-determining information, via a resistor15 a. As mentioned later, the first communicating unit 30A operates as atransmission-oriented unit based on the role-determining informationinputted from the tool main body 10 corresponding to the second powersupply voltage Vc2.

The first communicating unit 30A includes a communication circuit 31, acommunication controller 32, a power supplier 33, a button 34, a display35, and a connector 36. The button 34 receives a user manipulation.Specifically, the button 34 receives a pressing manipulation by a userto change (switch) a mode (operating mode) of the first communicatingunit 30A.

The connector 36 is coupled to the connector 16 of the tool main body10. The connector 36 includes a power-source terminal 36 a, a groundterminal 36 b, a role-determination terminal 36 c, an operational-signalterminal 36 d, three serial-communication terminals 36 e, 36 f, and 36g, and an auxiliary terminal 36 h.

The power-source terminal 36 a is coupled to the power supplier 33. Theground terminal 36 b is coupled to the ground line. The remaining sixterminals 36 c, 36 d, 36 e, 36 f, 36 g, and 36 h are coupled to thecommunication controller 32.

The connector 36 is coupled to the connector 16 as follows: thepower-source terminal 36 a is coupled to the power-source terminal 16 a;the ground terminal 36 b is coupled to the ground terminal 16 b; therole-determination terminal 36 c is coupled to the role-determinationterminal 16 c; and the operational-signal terminal 36 d is coupled tothe operational-signal terminal 16 d.

The first power supply voltage Vc1 generated in the tool main body 10 isdelivered to the first communicating unit 30A via the power-sourceterminal 36 a. In addition, the first power supply voltage Vc1 deliveredto the first communicating unit 30A is then delivered at least to thepower supplier 33 and the display 35.

The power supplier 33 generates a control voltage Vd based on thedelivered first power supply voltage Vc1. A value of the control voltageVd may be 3.3 volts for example. The control voltage Vd is used aspower-supply power for operating the components of the firstcommunicating unit 30A, including at least the communication circuit 31and the communication controller 32.

The communication circuit 31 receives and transmitswireless-communication radio wave that is in conformity with theaforementioned telecommunications standard (BLE, for example). Inaccordance with a transmission command from the communication controller32, the communication circuit 31 converts various data for transmission,delivered from the communication controller 32, into wireless signalsand wirelessly transmits the wireless signals to an outer subject. Thecommunication circuit 31 also converts wireless signals received from anouter subject into data and transmits the data to the communicationcontroller 32.

The communication controller 32 includes a microcomputer that includes aCPU 32 a, and a memory 32 b. The memory 32 b may include a semiconductormemory such as a RAM, a ROM, and a flash memory. The memory 32 b storesvarious programs and data for achieving various functions of the firstcommunicating unit 30A. These various functions of the firstcommunicating unit 30A are achieved by the CPU 32 a executing thevarious programs stored in the memory 32 b. Nevertheless, these variousfunctions achieved by the communication controller 32 may also beachieved partially or entirely by a hardware that includes a combinationof circuits, such as a logic circuit and an analog circuit, and does nothave to be achieved only by a software process.

The communication controller 32 is configured to function as thetransmission-oriented unit or as the search-oriented unit depending on adevice to which the first communicating unit 30A is attached.

The transmission-oriented unit transmits a wait-notice, aconjunction-notice, a registration-notice, and a deletion-noticeunilaterally and cyclically without specifying a recipient; that is, inother words, the transmission-oriented unit performs a regular wirelessbroadcasting of these notices. Cyclic transmissions of these notices arethose called “advertise” or “advertising” in BLE, for example.

The search-oriented unit (i) searches for the above notices transmittedfrom the transmission-oriented unit, (ii) receives any one of thenotices, and (iii) executes a process in accordance with the receivednotice.

The communication controller 32 operates as the transmission-orientedunit if the role-determining information corresponds to the second powersupply voltage Vc2. The communication controller 32 operates as thesearch-oriented unit if the delivered role-determining informationcorresponds to the voltage of the ground line.

In the present embodiment, the tool main body 10 is configured totransmit the second power supply voltage Vc2 as the role-determininginformation. Thus, the communication controller 32 operates as thetransmission-oriented unit when the first communicating unit 30A isattached to the tool main body 10.

The communication controller 32 operating as the transmission-orientedunit is set to one of a wait-transmission mode, aconjunction-transmission mode, a registration-transmission mode, and adeletion-transmission mode. The communication controller 32 operates inaccordance with the set mode.

The communication controller 32 in the wait-transmission mode performs awireless cyclic transmission (regular broadcasting) of the wait-noticeat a first transmission cycle Ttr1 via the communication circuit 31. Thewait-notice includes a first identification information that indicatethe first communicating unit 30A, and information indicating that thenotice in the transmission is the wait-notice. The first transmissioncycle Ttr1 may be 100 ms (“ms” is millisecond) for example.

The communication controller 32 in the conjunction-transmission modeperforms a wireless cyclic transmission (regular broadcasting) of theconjunction-notice at a second transmission cycle Ttr2 via thecommunication circuit 31. The conjunction-notice includes the firstidentification information, information indicating that the notice inthe transmission is the conjunction-notice, and machine-operationalinformation that indicate the operational state of the electric powertool 1. In the present embodiment, the machine-operational informationmay indicate a driving state of the saw blade 20, for example. Thesecond transmission cycle Ttr2 may be 30 ms for example.

The communication controller 32 in the registration-transmission modeperforms a wireless cyclic transmission (regular broadcasting) of theregistration-notice at a third transmission cycle Ttr3 via thecommunication circuit 31. The registration-notice includes the firstidentification information, and information indicating that the noticein the transmission is the registration-notice (this informationcorresponds to one example of registration information in the presentdisclosure). The third transmission cycle Ttr3 may be 100 ms forexample.

The communication controller 32 in the deletion-transmission modeperforms a wireless cyclic transmission (regular broadcasting) of thedeletion-notice at a fourth transmission cycle Ttr4 via thecommunication circuit 31. The deletion-notice includes the firstidentification information, and information indicating that the noticein the transmission is the deletion-notice (this information correspondsto one example of deletion information in the present disclosure). Thefourth transmission cycle Ttr4 may be 100 ms for example.

In the present embodiment, the second transmission cycle is shorter thanany of the first transmission cycle Ttr1, the third transmission cycleTtr3, and the fourth transmission cycle Ttr4. In the present embodiment,all of the wait-notice, the conjunction-notice, the registration-notice,and the deletion-notice are transmitted without specifying a recipientas mentioned above. In another embodiment, the recipient of at least oneof these notices may be specified.

For example, assume that another communicating unit configured tooperate as a transmission-oriented unit is present in addition to thefirst communicating unit 30A. In this case, if the regular broadcastingis performed by both of the first communicating unit 30A and the anothercommunicating unit at the same transmission cycle, then transmissions ofthe notice from these communicating units may cyclically andcontinuously overlap with each other, which may lead to cyclic andcontinuous collision of the transmitted notices. As a consequence, thenotices may fail to be received properly by the second communicatingunit 30B.

To reduce such collision of the notices, at least one of thetransmission cycles Ttr1, Ttr2, Ttr3, or Ttr4 may be set to a differentvalue for each of the first communicating unit 30A, the secondcommunicating unit 30B, and the additional communicating unit.

The first communicating unit 30A receives the aforementioneddriving-state signal or the aforementioned stop-state signal from thetool main body 10 via the operational-signal terminal 36 d.

The driving-state signal indicates that the motor 11 is being driven orthe saw blade 20 is rotating. The stop-state signal indicates that themotor 11 is stopped or the saw blade 20 is stopped.

The communication controller 32 in the conjunction-transmission modegenerates the machine-operational information based on the driving-statesignal or the stop-state signal delivered from the tool main body 10.More specifically, the communication controller 32 generatesdriving-state information as the machine-operational information whenthe communication controller 32 receives the driving-state signal; thecommunication controller 32 generates stop-state information as themachine-operational information when the communication controller 32receives the stop-state signal.

In other words, the conjunction-notice that includes either thedriving-state information or the stop-state information is cyclicallytransmitted from the first communicating unit 30A, in which thecommunication controller 32 is set to the conjunction-transmission mode.

As mentioned later, the dust collector 50 is driven in conjunction withthe electric power tool 1 when the conjunction-notice that includes thedriving-state information is received by the second communicating unit30B. More specifically, the fan 60 of the dust collector 50 is activatedin response to a drive of a later-described motor 51 (see FIG. 3) in thedust collector 50. This conjunctive operation of the dust collector 50is stopped when the conjunction-notice that includes the stop-stateinformation is received by the second communicating unit 30B after theconjunctive operation of the dust collector 50 is started. In otherwords, the fan 60 is stopped in response to stop of the drive of themotor 51.

The mode of the communication controller 32 changes by pressing thebutton 34 of the first communicating unit 30A. In other words, the usercan change the notice to be cyclically transmitted by the firstcommunicating unit 30A, by pressing the button 34 of the firstcommunicating unit 30A.

The display 35 is configured to use the first power supply voltage Vc1as the power-supply power for operation and to notify the operationstate of the first communicating unit 30A to an outer subject. In thepresent embodiment, the display 35 includes a first LED 35 a, a secondLED 35 b, and a third LED 35 c as shown in FIG. 4. For example, thefirst LED 35 a may emit a green light, the second LED 35 b may emit ablue light, and the third LED 35 c may emit a red light.

The communication controller 32 controls each of LED 35 a, 35 b, and 35c in accordance with the operational state of the first communicatingunit 30A. The communication controller 32 may control the LED 35 a, LED35 b, and LED 35 c in accordance with the operational state of the firstcommunicating unit 30A to at least one of seven example light-emittingpatterns shown in FIG. 4, for example.

(1-3) Electrical Configuration of Dust Collector and SecondCommunicating Unit

An electrical configuration of the dust collector 50 will be explainednext with reference to FIG. 3. FIG. 3 shows the dust collector 50, withthe second communicating unit 30B attached thereto. In this embodiment,a configuration of the second communicating unit 30B is the same as theconfiguration of the first communicating unit 30A as shown in FIG. 2.The second communicating unit 30B is different from the firstcommunicating unit 30A in terms of information to be input and outputvia the connector 36, and the mode to be set to the communicationcontroller 32 since the second communicating unit 30B is attached to thedust collector 50.

The dust collector 50 includes the motor 51, a main controller 52, apower supplier 53, a role-determiner 55, a connector 56, the fan 60, anda plug 70.

The connector 56 is coupled to the connector 36 of the secondcommunicating unit 30B. The connector 56 includes a power-sourceterminal 56 a, a ground terminal 56 b, a role-determination terminal 56c, and an operational-signal terminal 56 d.

The power-source terminal 56 a is coupled to an output terminal of thefirst power supply voltage Vc1 in the power supplier 53. The groundterminal 56 b is coupled to the ground line. The role-determinationterminal 56 c is coupled to the role-determiner 55. Theoperational-signal terminal 56 d is coupled to the main controller 52.

The connector 36 of the second communicating unit 30B is coupled to theconnector 56 of the dust collector 50 as follows: the power-sourceterminal 36 a is coupled to the power-source terminal 56 a; the groundterminal 36 b is coupled to the ground terminal 56 b; therole-determination terminal 36 c is coupled to the role-determinationterminal 56 c, and the operational-signal terminal 36 d is coupled tothe operational-signal terminal 56 d. The first power supply voltage Vc1generated in the dust collector 50 is delivered to the secondcommunicating unit 30B via the power-source terminal 56 a.

The motor 51 drives the fan 60. The power supplier 53 receives AC powersupplied from an outside power source (such as a commercial powersource) via the plug 70 and, based on the AC power, generatespower-supply power to operate each component in the dust collector 50.

More specifically, the power supplier 53 generates the first powersupply voltage Vc1 and the second power supply voltage Vd2 based on theAC power delivered via the plug 70. The first power supply voltages Vc1and the second power supply voltage Vd2 are used as power-supply powerfor operating each component in the dust collector 50. The first powersupply voltage Vc1 can be supplied from the power-source terminal 56 ato an outer subject.

The dust collector 50 may be configured to be operable by direct-current(DC) power from a battery in a battery pack by having a configuration toallow the battery pack to be attached to and detached from the dustcollector 50 like the electric power tool 1, or from a built-in batteryby having a configuration to include the built-in battery.

The motor 51 may be any type of motor The motor 51 may be a brushed DCmotor, a brushless DC motor, or another type of motor.

The main controller 52 includes a microcomputer that includes a CPU 61,and a memory 62. The memory 62 may include a semiconductor memory suchas a RAM, a ROM, and a flash memory. The memory 62 stores variousprograms and data for the CPU 61 to read out and execute to achievevarious functions of the dust collector 50.

These various functions may be achieved partially or entirely by ahardware that includes a combination of circuits, such as a logiccircuit and an analog circuit, and does not have to be achieved only bya software process.

In response to turning on of a manipulation switch (not shown) of thedust collector 50, the main controller 52 rotates the fan 60 by drivingthe motor 51. Occasionally, as explained later, the main controller 52receives a conjunction command from the second communicating unit 30Bvia the operational-signal terminal 56 d. The main controller 52 rotatesthe fan 60 also by driving the motor 51 in an occasion of receiving theconjunction command.

The role-determiner 55 transmits the role-determining information to thesecond communicating unit 30B. In the present embodiment, therole-determiner 15 transmits, for example, the voltage of the groundline as the role-determining information.

The communication controller 32 of the second communicating unit 30Boperates as the search-oriented unit since the role-determininginformation delivered from the dust collector 50 corresponds to thevoltage of the ground line.

The communication controller 32 operating as the search-oriented unit isset to any one of a wait-search mode, a conjunction-search mode, aregistration-search mode, and a deletion-search mode. The communicationcontroller 32 operates in accordance with the set mode.

The communication controller 32 in the wait-search mode cyclicallysearches (or scans) the wait-notice. More specifically, thecommunication controller 32 cyclically determines whether thecommunication circuit 31 receives the wait-notice at a first intervalTin1. The first interval Tin1 may be 340 ms for example. The firstinterval Tin1 includes a first window Tw1. The first window Tw1 is atime period in which an actual determination is made on whether thewait-notice is received. The first window Tw1 may be 100 ms for example.

The communication controller 32 in the conjunction-search modecyclically searches the conjunction-notice at a second interval Tin2.The second interval Tin2 may be 140 ms for example. The second intervalTin2 includes a second window Tw2. The second window Tw2 is a timeperiod in which an actual determination is made on whether theconjuction-notice is received. The second window Tw2 may be 100 ms forexample.

The communication controller 32 in the registration-search modecyclically searches the registration-notice at a third interval Tin3.The third interval Tin3 may be 65 ms for example. The third intervalTin3 includes a third window Tw3. The third window Tw3 is a time periodin which an actual determination is made on whether theregistration-notice is received. The third window Tw3 may be 60 ms forexample.

The communication controller 32 in the deletion-search mode cyclicallysearches the deletion-notice at a fourth interval Tin4. The fourthinterval Tin4 may be 65 ms for example. The fourth interval Tin4includes a fourth window Tw4. The fourth window Tw4 is a time period inwhich an actual determination is made on whether the deletion-notice isreceived. The fourth window Tw4 may be 60 ms for example.

In the present embodiment, the second interval Tin2 may be set shorterthan the first interval Tin1. The third interval Tin3 may be set shorterthan any one of the first interval Tin1 and the second interval Tin2.Similarly, the fourth interval Tin4 may be set shorter than any one ofthe first interval Tin1 and the second interval Tin2. The third windowTw3 may be set shorter than any one of the first window Tw1 and thesecond window Tw2. Similarly, the fourth window Tw4 may be set shorterthan any one of the first window Tw1 and the second window Tw2.

In response to the button 34 pressed in the second communicating unit30B, the communication controller 32 changes its mode (its operatingmode). The user can change the notices to be searched by pressing thebutton 34 of the second communication unit 30B.

Every time the communication circuit 31 receives the conjunction-notice,the communication controller 32 in the conjunction-search modedetermines the detail of the received conjunction-notice. If thereceived conjuction-notice includes the aforementioned driving-stateinformation, and the first identification information included in thereceived conjunction-notice is registered in the second communicatingunit 30B, then the communication controller 32 transmits the conjunctioncommand via the operational-signal terminal 36 d. The conjunctioncommand is then delivered to the main controller 52 of the dustcollector 50 and causes the dust collector 50 to operate in conjunctionwith the electric power tool 1.

After transmitting the conjuction command, the communication controller32 transmits a stop command via the operational-signal terminal 36 dwhen the conjuction-notice including the stop-state information isreceived. In response to the stop command, the main controller 52 of thedust collector 50 stops the motor 51 to thereby stop the fan 60.

The main controller 52 may stop the motor 51 at any timing in responseto the delivery of the stop command to the main controller 52. Forexample, the main controller 52 may immediately stop the motor 51 inresponse to the delivery of the stop command. Alternatively, the maincontroller 52 may keep driving the motor 51 for a predefined time periodin response to the delivery of the stop command, and may stop the motor51 in response to the predefined time period elapsed.

(1-4) Example Operation of First Communicating Unit

An example operation of the first communicating unit 30A attached to theelectric power tool 1, in other words, an example operation of the firstcommunicating unit 30A as the transmission-oriented unit, will bedescribed with reference to FIG. 5. The description will be given by wayof example assuming that the first communication unit 30A can performwireless communications with the second communication unit 30B.

As shown in FIG. 5, in a state where the first communicating unit 30Astops its operation due to, for example, no supply of the power-supplypower to the first communicating unit 30A, all of the LEDs 35 a, 35 b,and 35 c of the display 35 are turned off (M101). When the firstcommunicating unit 30A is supplied with the first power supply voltageVc1 from the electric power tool 1, the first communicating unit 30A isactivated (thus the communication controller 32 is activated) (M102).

The activated communication controller 32 activates the communicationcircuit 31 (M102). Specifically, the communication controller 32performs a given activation process to activate the communicationcircuit 31 for a duration of an activation time Ts (about 3 seconds, forexample). During the activation process, the communication controller 32turns the third LED 35 c on in the display 35.

Also in M102, the communication controller 32 determines which role ofthe transmission-oriented unit or the search-oriented unit thecommunication controller 32 takes on based on the role-determininginformation delivered from the role-determination terminal 36 c. Due tothe role-determining information corresponding to the second powervoltage Vc2, the communication controller 32 determines that thecommunication controller 32 takes on the role of thetransmission-oriented unit. Thus, after the activation process, thecommunication controller 32 sets itself to the wait-transmission mode(M103).

In the wait-transmission mode, the communication controller 32unilaterally transmits the wait-notice (regular broadcasting) at thefirst transmission cycle Ttr1 via the communication circuit 31. Morespecifically, the communication controller 32 commands the communicationcircuit 31 to regularly broadcast the wait-notice. The communicationcontroller 32 itself shifts into a sleep state, in which powerconsumption is reduced compared with normal states. The communicationcontroller 32 turns on all of the LEDs 35 a, 36 b, and 36 c of thedisplay 35 during the wait-transmission mode.

During the wait-transmission mode, the user may change the mode of thecommunication controller 32 by pressing the button 34 (e.g. perfoming ashort press, a long press, or an extra-long press).

The short press is a manipulation for which the user keeps pressing thebutton 34 for a time period less than a first press-time Ta1 (200milliseconds, for example). The long press is a manipulation for whichthe user keeps pressing the button 34 for a time period equal to orlonger than the first press-time Ta1 but less than a second press-timeTa2 (3 seconds, for example). The extra-long press is a manipulation forwhich the user keeps pressing the button 34 for a time period equal toor longer than the second press-time Ta2 but less than a thirdpress-time Ta3 (6 seconds, for example).

In response to the short press on the button 34 in the wait-transmissionmode (M103), the communication controller 32 changes its mode to theconjunction-transmission mode (M104).

In the conjunction-transmission mode, the communication controller 32unilaterally transmits (regular broadcasting) the conjunction-notice atthe second transmission cycle Ttr2.

The communication controller 32 also turns on or flashes the second LED35 b during the conjunction-transmission mode. More specifically, thecommunication controller 32 flashes the second LED 35 b when thestop-state signal is delivered from the tool main body 10, which is whenthe communication controller 32 is wirelessly transmitting thestop-state information as the machine-operational information. Thecommunication controller 32 turns on the second LED 35 b when thedriving-state signal is delivered from the tool main body 10, which iswhen the communication controller 32 is wirelessly transmitting thedriving-state information as the machine-operational information.

In the conjunction-transmission mode (M104), if the button 34 receivesthe short press, or if a time Tn (2 hours, for example) or longer haselapsed without a delivery of the driving-state signal from the toolmain body 10, the communication controller 32 changes its mode to thewait-transmission mode (M103).

If the button 34 receives the long press in the wait-transmission mode(M103) or the conjunction-transmission mode (M104), then thecommunication controller 32 changes its mode to theregistration-transmission mode (M105). In the registration-transmissionmode, the communication controller 32 unilaterally transmits (regularbroadcasting) the registration-notice at the third transmission cycleTtr3 via the communication circuit 31. In the registration-transmissionmode, the communication controller 32 flashes the first LED 35 a.

If a first connection request is delivered from the second communicatingunit 30B in response to the transmitted registration-notice in theregistration-transmission mode (M105), then the communication controller32 stops the regular transmission of the registration-notice andestablishes a connection with the second communicating unit 30B (M106).Once the connection with the second communicating unit 30B isestablished, the second communicating unit 30B transmits a secondidentification information indicating the second communicating unit 30B,and the communication controller 32 executes a first registrationprocess (M106).

The second communicating unit 30B in the registration-search modetransmits the first connection request in response to receipt of theregistration-notice.

The first registration process is a process to store the secondidentification information received via the communication circuit 31 inthe memory 32 b to thereby register the second identificationinformation (thus the second communicating unit 30B). The firstregistration process may include a process to transmit the firstidentification information via the communication circuit 31. In a casewhere the first registration process is performed in the firstcommunicating unit 30A, the first identification information (thus thefirst communicating unit 30A) is registered in the second communicatingunit 30B as described below. More specifically, in a case where thefirst identification information is “A0” and the second identificationinformation is “B1”, for example, the second identification information“B1” is registered in the first communicating unit 30A and the firstidentification information “A0” is registered in the secondcommunicating unit 30B.

During the execution of the first registration process, thecommunication controller 32 flashes the first LED 35 a (M106). Once theregistration process is completed, the communication controller 32 keepsthe first LED 35 a on (M107). The communication controller 32 then endsthe connection with the second communicating unit 30B, completes thedata communication, and changes its mode to the conjunction-transmissionmode (M104).

If the button 34 receives the short press or if a first timeout occursin the registration-transmission mode (M105), then the communicationcontroller 32 changes its mode to the conjunction-transmission mode(M104). The first timeout means that a first time period (20 seconds,for example) elapses without receiving the first connection request.

If the radio wave from the second communicating unit 30B fails to bereceived or if a second timeout occurs after the first connectionrequest from the second communicating unit 30B is received in theregistration-transmission mode (M106), then the communication controller32 changes its mode to the conjunction-transmission mode (M104). Thesecond timeout means that a second time period elapses without properlycompleting the first registration process albeit the radio wave from thesecond communicating unit 30B is received (in other words, theconnection with the second communicating unit 30B is maintained).

If a first mobile connection request is received from the mobile device100 in the registration-transmission mode (M105), then the communicationcontroller 32 stops the regular transmission of the registration-notice,establishes a connection with the mobile device 100, and performs a datacommunication with the mobile device 100 (M108). If the datacommunication with the mobile device 100 is completed or if the radiowave from the mobile device 100 fails to be received or if a thirdtimeout occurs, then the communication controller 32 changes its mode tothe wait-transmission mode (M103). The third timeout means that a thirdtime period elapses without properly completing the data communicationwith the mobile device 100 albeit the radio wave1 from the mobile device100 is received (in other words, the connection with the mobile device100 is maintained).

If the button 34 receives the extra-long press in the wait-transmissionmode (M103) or in the conjunction-transmission mode (M104), then thecommunication controller 32 changes its mode to thedeletion-transmission mode (M109). In the deletion-transmission mode,the communication controller 32 unilaterally transmits (regularbroadcasting) the deletion-notice at the fourth transmission cycle Ttr4via the communication circuit 31. In the deletion-transmission mode, thecommunication controller 32 flashes the third LED 35 c.

If the second connection request is delivered from the secondcommunicating unit 30B in response to the transmitted deletion-notice inthe deletion-transmission mode (M109), the communication controller 32stops the regular transmission of the deletion-notice and establishes aconnection with the second communicating unit 30B (M110). Once theconnection with the second communicating unit 30B is established, thecommunication controller 32 executes a first deletion process (M110).

The second communicating unit 30B in the deletion-search mode transmitsthe second connection request in response to receipt of thedeletion-notice.

The first deletion process is a process to delete the secondidentification information stored in the memory 32 b, for example, tothereby delete the registration of the second communicating unit 30B. Ina case where the first deletion process is performed in the firstcommunicating unit 30A, the first identification information is deleted(in other words, the registration of the first communicating unit 30A isdeleted)

During the execution of the first deletion process, the communicationcontroller 32 flashes the third LED 35 c (M110). Once the first deletionprocess is completed, the communication controller 32 keeps the thirdLED 35 c on (M111). The communication controller 32 then ends theconnection with the second communicating unit 30B, completes the datacommunication, and changes its mode to the conjunction-transmission mode(M104).

If the button 34 receives the short press or if a fourth timeout occursin the deletion-transmission mode (M109), then the communicationcontroller 32 changes its mode to the conjunction-transmission mode(M104). If the radio wave from the second communicating unit 30B failsto be received or a fifth timeout occurs after the second connectionrequest from the second communicating unit 30B is received in thedeletion-transmission mode (M110), then the communication controller 32changes its mode to the conjunction-transmission mode (M104). In a casewhere an additional communicating unit operating as the search-orientedunit exists in addition to the second communicating unit 30B, the firstcommunicating unit 30A can perform a wireless communication with theadditional communicating unit in a similar manner to the wirelesscommunication with the second communicating unit 30B.

(1-5) Example Operation of Second Communicating Unit

An example operation of the second communicating unit 30B attached tothe dust collector 50, in other words, an example operation of thesecond communicating unit 30B operating as the search-oriented unit,will be explained with reference to FIG. 6. The description will begiven by way of example assuming that the second communication unit 30Bcan perform wireless communications with the first communication unit30A.

The state where the second communicating unit 30B stops its operationdue to no supply of the power-supply power to the second communicatingunit 30B, for example (M201), and the state where the communicationcontroller 32 performs the activation process to activate thecommunication circuit 31 (M202) are respectively the same as M101 andM102 in FIG. 5.

In M202, the communication controller 32 determines that thecommunication controller 32 takes on the role of the search-orientedunit since the role-determining information delivered from the dustcollector 50 corresponds to the voltage of the ground line. Thus, afterthe activation process, the communication controller 32 sets its mode tothe wait-search mode (M203).

In the wait-search mode, the communication controller 32 cyclicallysearches for the wait-notice via the communication circuit 13 at thefirst interval Tin1 and for the first window Tw1. The communicationcontroller 32 flashes the second LED 35 b during the wait-search mode.

In the wait-search mode, if the conjunction-notice is received and ifthe first identification information included in the conjunction-noticeis registered in the second communicating unit 30B, then thecommunication controller 32 changes its mode to the conjunction-searchmode (M204).

In the conjunction-search mode, the communication controller 32cyclically searches for the conjunction-notice at the second intervalTin2 and for the second window Tw2. Every time the communicationcontroller 32 receives the conjunction-notice including the firstidentification information registered in the second communicating unit30B, the communication controller 32 determines whether the dustcollector 50 should operate in conjunction with the electric power tool1 based on the machine-operational information included in theconjunction-notice.

More specifically, the communication controller 32 transmits the stopcommand to the dust collector 50 via the operational-signal terminal 36d to prevent the conjunctive operation if the machine-operationalinformation includes the stop-state information. The communicationcontroller 32 transmits the conjunction command to the dust collector 50via the operational-signal terminal 36 d to cause the conjunctiveoperation if the machine-operational information includes thedriving-state information.

The communication controller 32 flashes the second LED 35 b when theconjunction-notice including the stop-state information is received (inother words, when the communication controller 32 prevents theconjunctive operation) during the conjunction-search mode. Thecommunication controller 32 turns the second LED 35 b on when theconjunction-notice including the driving-state information is received(in other word, when the communication controller 32 allows the dustcollector 50 for the conjunctive operation).

In the conjunction-search mode, if a time Tz (2 hours, for example) orlonger has elapsed without a delivery of the driving-state information,then the communication controller 32 changes its mode to the wait-searchmode (M203).

If the button 34 receives the long press in the wait-search mode (M203)or the conjunction-search mode (M204), then the communication controller32 changes its mode to the registration-search mode (M205). In theregistration-search mode, the communication controller 32 cyclicallysearches for the registration-notice at the third interval Tin3 and forthe third window Tw3. In the registration-search mode, the communicationcontroller 32 also flashes the first LED 35 a.

If the registration-notice is delivered from the first communicatingunit 30A in the registration-search mode, the communication controller32 transmits the aforementioned first connection request to the firstcommunicating unit 30A to thereby establish a connection with the firstcommunicating unit 30A (M206). Once the connection with the firstcommunicating unit 30A is established, the communication controller 32executes the second registration process. In other words, thecommunication controller 32 stores the first identification informationincluded in the delivered registration-notice in the memory 32 tothereby register the first identification information (thus the firstcommunicating unit 30A). The communication controller 32 also transmitsthe second identification information to the first communicating unit30A (M206).

During the execution of the second registration process, thecommunication controller 32 flashes the first LED 35 a (M206). Once thesecond registration process is completed, the communication controller32 keeps the first LED 35 a on (M207). The communication controller 32then ends the connection with the first communicating unit 30A,completes the data communication, and changes its mode to theconjunction-search mode (M204).

If the button 34 receives the short press or if a sixth timeout occursin the registration-search mode (M205), then the communicationcontroller 32 changes its mode to the conjunction-search mode (M204). Ifthe radio wave from the first communicating unit 30A fails to bereceived or if a seventh timeout occurs after the registration-noticefrom the first communicating unit 30A is received in theregistration-search mode (M206), then the communication controller 32changes its mode to the conjunction-search mode (M204).

If the button 34 receives the long press in the registration-search mode(M205), the communication controller 32 operates as thetransmission-oriented unit. More specifically, the communicationcontroller 32 changes its mode to a mobile-connection transmission mode(M208).

In the mobile-connection transmission mode, the communication controller32 cyclically performs a wireless transmission (regular broadcasting) ofa mobile-connection notice. The mobile-connection notice includes thesecond identification information, and information indicating that thenotice in the transmission is the mobile-connection notice.

If the mobile-connection notice is received by the mobile device 100,then the mobile device 100 transmits the second mobile connectionrequest. In response to receipt of the second mobile connection requestfrom the mobile device 100, the communication controller 32 establishesa connection with the mobile device 100 and performs a datacommunication with the mobile device 100 (M209).

If the data communication with the mobile device 100 is completed or ifthe radio wave from the mobile device 100 fails to be received or if aeighth timeout occurs, then the communication controller 32 changes itsmode to the wait-search mode (M203).

If the button 34 receives the short press or if a ninth timeout occursin the mobile-connection transmission mode (M208), then thecommunication controller 32 changes its mode to the wait-search mode(M203). The ninth timeout means that a given time period elapses withoutreceiving the second mobile connection request from the mobile device100.

If the button 34 receives the extra-long press in the wait-search mode(M203) or in the conjunction-search mode (M204), then the communicationcontroller 32 changes its mode to the deletion-search mode (M210). Inthe deletion-search mode, the communication controller 32 cyclicallysearches for the deletion-notice at the fourth interval Tin4 and for thefourth window Tw4. The communication controller 32 also flashes thethird LED 35 c during the deletion-search mode.

If the deletion-notice is delivered from the first communicating unit30A in the deletion-search mode, then the communication controller 32transmits the aforementioned second connection request to the firstcommunicating unit 30A to thereby establish a connection with the firstcommunicating unit 30A (M211). Once the connection with the firstcommunicating unit 30A is established, the communication controller 32executes the second deletion process (M211). In other words, thecommunication controller 32 deletes the first identification informationfrom the memory 32 b to thereby delete the registration of the firstidentification information (thus the registration of the firstcommunicating unit 30A).

During the execution of the second deletion process, the communicationcontroller 32 flashes the third LED 35 c (M211). Once the seconddeletion process is completed, the communication controller 32 keeps thethird LED 35 c on (M212). The communication controller 32 then ends theconnection with the first communicating unit 30A, completes the datacommunication, and changes its mode to the conjunction-search mode(M204).

If the button 34 receives the short press or if a tenth timeout occursin the deletion-search mode (M210), then the communication controller 32changes its mode to the conjunction-search mode (M204). If the radiowave from the first communicating unit 30A fails to be received or if aeleventh timeout occurs after the deletion-notice from the firstcommunicating unit 30A is received in the deletion-search mode, then thecommunication controller 32 changes its mode to the conjunction-searchmode (M204).

If the button 34 receives the extra-long press in the deletion-searchmode (M210), then the communication controller 32 deletes registrationof all of the registered identification information (M213). In a casewhere only the first identification information is registered, forexample, the registration of only the first identification informationis deleted. In a case where, in addition to the first identificationinformation, an additional identification information of an additionalcommunicating unit is registered, for example, not only the registrationof the first identification information but also the registration of theadditional identification information is deleted. During deletion ofregistration of all of the registered identification information (M213),the communication controller 32 turns on the third LED 35 c. Thecommunication controller 32 then changes its mode to the wait-searchmode (M203) after the deletion of registration of all of the registeredidentification information. In a case where an additional communicatingunit operating as the search-oriented unit exists in addition to thesecond communicating unit 30B, the additional communicating unit canperform a wireless communication with the first communicating unit 30Ain a similar manner to the wireless communication with the secondcommunicating unit 30B.

(1-6) Explanation of Communication Control Process

A communication control process executed by each of the communicationcontroller 32 in the first communicating unit 30A and the communicationcontroller 32 in the second communicating unit 30B will be explainednext with reference to FIGS. 7A and 7B. The example operation shown inFIG. 5 is achieved by the communication controller 32 in the firstcommunicating unit 30A executing the communication control process. Theexample operation shown in FIG. 6 is achieved by the communicationcontroller 32 in the second communicating unit 30B executing thecommunication control process. In a case where the first communicatingunit 30A is attached to the dust collector 50 and the secondcommunicating unit 30B is attached to the electric power tool 1, thefirst communicating unit 30A operates in the same manner as the secondcommunicating unit 30B attached to the dust collector 50 operates, thesecond communicating unit 30B operates in the same manner as the firstcommunicating unit 30A attached to the electric power tool 1 operates.

The memory 32 b stores a program for the communication control process.After activation, the communication controller 32 (more specifically,the CPU 32 a) reads out the program of the communication control processfrom the memory 32 b and executes the program. FIGS. 7A and 7Bschematically show the communication control process for convenience ofexplanation. The operations exemplified in FIG. 5 and FIG. 6 aretherefore partially omitted in FIGS. 7A and 7B.

The communication controller 32 executes an initial process in S110 oncethe communication control process begins. The initial process includesthe aforementioned activation process to activate the communicationcircuit 31. In the initial process, the communication controller 32determines which role of the transmission-oriented unit or thesearch-oriented unit the communication controller 32 takes on based onthe role-determining information. In S110, the communication controller32 turns on the third LED 35 c.

In S120, the communication controller 32 determines which role of thetransmission-oriented unit or the search-oriented unit the communicationcontroller 32 takes on based on the determination result in the initialprocess in S110. If the communication controller 32 determines to takeon the role of the transmission-oriented unit, then the process proceedsto S130. In S130, the communication controller 32 sets its mode to thewait-transmission mode. In response to the communication controller 32being set in the wait-transmission mode, the communication controller 32performs a regular transmission of the wait-notice at the firsttransmission cycle Ttr1. In S130, the communication controller 32 turnsoff all of the LEDs 35 a, 35 b, and 35 c.

In S140, the communication controller 32 determines whether the button34 receives the short press. If the communication controller 32determines that the button 34 receives the short press, then thecommunication controller 32 sets its mode to theconjunction-transmission mode in S150. In response to the communicationcontroller 32 being set in the conjunction-transmission mode, thecommunication controller 32 performs a regular transmission of theconjunction-notice at the second transmission cycle Ttr2. In S150, thecommunication controller 32 flashes or turns on the second LED 35 bbased on the machine-operational information.

In S160, the communication controller 32 determines whether a firstcondition is satisfied. The first condition is a condition for thecommunication controller 32 to return its mode to the wait-transmissionmode from the conjunction-transmission mode. If the first condition issatisfied, then the process proceeds to S130. If the first condition isnot satisfied, then the process proceeds to S170.

In S170, the communication controller 32 determines whether a secondcondition or a third condition is satisfied. The second condition is acondition for the communication controller 32 to change its mode fromthe conjunction-transmission mode to the registration-transmission mode.The second condition is satisfied in response to the button 34 receivingthe long press, for example. The third condition is a condition for thecommunication controller 32 to change its mode from theconjunction-transmission mode to the deletion-transmission mode. Thethird condition is satisfied in response to the button 34 receiving theextra-long press, for example. If neither the second condition nor thethird condition is satisfied, then the process proceeds to S150. Ifeither the second condition or the third condition is satisfied, theprocess proceeds to S180.

In S180 the communication controller 32 changes its mode to theregistration-transmission mode or to the deletion-transmission mode,depending on the condition that is satisfied in S170. In S180, thecommunication controller 32 also controls the display 35 in accordancewith its changed mode. In addition, the communication controller 32 inthe registration-transmission mode executes the first registrationprocess in response to receipt of the first connection request; thecommunication controller 32 in the deletion-transmission mode executesthe first deletion process in response to receipt of the secondconnection request. In response to a condition for the communicationcontroller 32 to change its mode to the conjunction-transmission modebeing satisfied when the communication controller 32 is in theregistration-transmission mode or the deletion-transmission mode, theprocess proceeds to S150.

If the button 34 does not receive the short press in S140, then theprocess proceeds to S190. In S190, the communication controller 32determines whether a fourth condition or a fifth condition is satisfied.The fourth condition is a condition for the communication controller32to change its mode from the wait-transmission mode to theregistration-transmission mode. The fourth condition is satisfied inresponse to the button 34 receiving the long press, for example. Thefifth condign is a condition for the communication controller 32 tochange its mode from the wait-transmission mode to thedeletion-transmission mode. The fifth condition is satisfied in responseto the button 34 receiving the extra-long press. If neither the fourthcondition nor the fifth condition is satisfied, then the process returnsto S130. If either the fourth condition or the fifth condition issatisfied, then the process proceeds to S200. The process in S200 is thesame as the process in S180.

In S120, if the communication controller 32 determines that thecommunication controller 32 takes on the role of the search-orientedunit, then the process proceeds to S210. In S210, the communicationcontroller 32 sets its mode to the wait-search mode. The communicationcontroller 32 cyclically searches for the wait-notice in response to thecommunication controller 32 being set in the wait-search mode. In S210,the communication controller 32 flashes the second LED 35 b.

In S220, the communication controller 32 determines whether theconjunction-notice is received. If the conjunction-notice is received,then the communication controller 32 sets its mode to theconjunction-search mode in S230. In response to the communicationcontroller 32 being set to the conjunction-search mode, thecommunication controller 32 cyclically searches for theconjunction-notice. In S230, the communication controller 32 flashes orturns on the second LED 35 b based on the machine-operationalinformation included in the received conjunction-notice. Thecommunication controller 32 also transmits the conjunction command orstop command based on the machine-operational information included inthe received conjunction-notice in S230.

In S240, the communication controller 32 determines whether a sixthcondition is satisfied. The sixth condition is a condition for thecommunication controller 32 to return its mode to the wait-search modefrom the conjunction-search mode. If the sixth condition is satisfied,then the process proceeds to S210. If the sixth condition is notsatisfied, then the process proceeds to S250.

In S250, the communication controller 32 determines whether a seventhcondition or an eighth condition is satisfied. The seventh condition isa condition for the communication controller to change its mode from theconjunction-search mode to the registration-search mode. The seventhcondition is satisfied in response to the button 34 receiving the longpress, for example. The eighth condition is a condition for thecommunication controller 32 to change its mode from theconjunction-search mode to the deletion-search mode. The eighthcondition is satisfied in response to the button 34 receiving theextra-long press. If neither the seventh condition nor the eighthcondition is satisfied, then the process returns to S230. If either theseventh condition or the eighth condition is satisfied, then the processproceeds to S260.

In S260, the communication controller 32 changes its mode to theregistration-search mode or to the deletion-search mode, depending onthe condition that is satisfied in S250. In S260, the communicationcontroller 32 also controls the display 35 in accordance with thechanged mode. In addition, the communication controller 32 in theregistration-search mode executes the second registration process inresponse to receipt of the registration-notice; the communicationcontroller 32 in the deletion-search mode executes the second deletionprocess in response to receipt of the deletion-notice. In response to acondition for the communication controller 32 to change its mode to theconjunction-search mode being satisfied when the communicationcontroller 32 is in the registration-search mode or the deletion-searchmode, the process proceeds to S230.

If the conjunction-notice is not received in S220, the process proceedsto S270. In S270, the communication controller 32 determines whether aninth condition or a tenth condition is satisfied. The ninth conditionis a condition for the communication controller 32 to change its modefrom the wait-search mode to the registration-search mode. The ninthcondition is satisfied in response to the button 34 receiving the longpress,for example. The tenth condition is a condition for thecommunication controller 32 to change its mode from the wait-search modeto the deletion-search mode. The tenth condition is satisfied inresponse to the button 34 receiving the extra-long press, for example.If neither the ninth condition nor the tenth condition is satisfied,then the process returns to S210. If either the ninth condition or thetenth condition is satisfied, then the process proceeds to S280. Theprocess in S280 is the same as the process in S260.

The first communicating unit 30A corresponds to an example of thecommunicator in the present disclosure and an example of the secondadditional communicator in the present disclosure. The secondcommunicating unit 30B corresponds to an example of the communicator inthe present disclosure and an example of the first additionalcommunicator. The second communicating unit 30B corresponds to anexample of the first additional communicator. The first electric workingmachine 1 (electric power tool 1) corresponds to an example of thetransmission side electric working machine in the present disclosure.The second electric working machine 50 (dust collector 50) correspondsto an example of the receiving side electric working machine in thepresent disclosure. The saw blade 20 corresponds to an example of thetool of the transmission side electric working machine in the presentdisclosure. The fan 60 corresponds to an example of the tool of thereceiving side electric working machine in the present disclosure. Themotor 11 in the electric power tool 1 corresponds to an example of thedriving device (the transmission side driving device) configured todrive the tool of the transmission side electric working machine in thepresent disclosure. The motor 51 in the dust collector 50 corresponds tothe driving device (the receiving side driving device) configured todrive the tool of the receiving side electric working machine in thepresent disclosure. The connector 36 corresponds to an example of theconnector in the present disclosure. The button 34 corresponds to anexample of the manipulator on the present disclosure. Theconjunction-transmission mode corresponds to an example of theoperation-transmission mode in the present disclosure. Theconjunction-search mode corresponds to an example of operation-receivingmode in the present disclosure. The wait-search mode corresponds to anexample of the wait-receiving mode in the present disclosure. Theregistration-search mode corresponds to an example of theregistration-receiving mode in the present disclosure. Thedeletion-search mode corresponds to an example of the deletion-receivingmode in the present disclosure. The second transmission cycle Ttr2corresponds to an example of the first transmission cycle in the presentdisclosure. The first transmission cycle Ttr1, the third transmissioncycle Ttr3, and the fourth transmission cycle Ttr4 correspond to anexample of the second transmission cycle in the present disclosure. Thesecond interval Tin2 in the conjunction-search mode corresponds to anexample of the first monitoring cycle in the present disclosure. Thefirst interval Tin1 in the wait-search mode corresponds to an example ofthe second monitoring cycle in the present disclosure. Themachine-operational information corresponds to an example of theoperational information in the present disclosure. The firstidentification information included in the registration-noticecorresponds to an example of the first communicator information and thesecond communicator information in the present disclosure. The sevenlight-emitting patterns exemplified in FIG. 4 correspond to an exampleof the mode information and the driving information in the presentdisclosure.

2. Other Embodiments

Although one embodiment of present disclosure is as explained above, thepresent disclosure is not limited to the aforementioned embodiment andmay be modified in various formes.

(2-1) The aforementioned four modes set in the transmission-orientedunit (the wait-transmission mode, the conjunction-transmission mode, theregistration-transmission mode, and the deletion-transmission mode) aremerely examples. The transmission-oriented unit may be set in any typesof mode.

The aforementioned four modes set in the search-oriented unit (thewait-search mode, the conjunction-search mode, the registration-searchmode, and the deletion-search mode) are merely examples. Thesearch-oriented unit may be set in any types of mode.

(2-2) Two types of the role-determining information, the second powersupply voltage Vc2 and the voltage of the ground line, are described inthe aforementioned embodiment. These are also merely examples. There maybe other role-determining information. The first communicating unit 30Aand the second communicating unit 30B may operate or function in anymanner in response to the role-determining information inputted. Forexample, there may be an additional device that includes avoltage-dividing circuit to divide the second power supply voltage Vc2and transmits the divided voltage as role-determining information.

In this case, the first communicating unit 30A to which the dividedvoltage is delivered as the role-determining information may relay datacommunication between a device to which the first communicating unit 30Ais attached, and an additional device. In this case, the firstcommunicating unit 30A may perform data communication through the threedata communication terminals 36 e, 36 f, and 36 g between the firstcommunicating unit 30A and the device to which the first communicatingunit 30A is attached.

(2-3) In each of the first communicating unit 30A and the secondcommunicating unit 30B, the communication controller 32 and thecommunication circuit 31 may be integrated.

In addition, the first communicating unit 30A may be included in thefirst electric working machine 1 as a built-in unit. The secondcommunicating unit 30B may be included in the second electric workingmachine 50 as a built-in unit.

(2-4) In the aforementioned embodiment, the electric power tool 1 andthe dust collector 50 were given as examples of the electric workingmachine. Nevertheless, the technique of the present disclosure may beapplied to various jobsite electric apparatus equipped withelectrically-driven tools including other types of electric workingmachines. Those jobsites may include a home carpentry site, amanufacturing site, a gardening site, and a construction site.

To be specific, the technique of the present disclosure may be appliedto various electric working machines equipped with a tool, for example,electric power tools for stone processing, metal processing, or woodprocessing; machinery for gardening; and machinery for creating betterjobsite environment. To be more specific, the technique of the presentdisclosure may be applied to various electric working machines such aselectric hammers, electric hammer drills, electric drills, electricscrewdrivers, electric wrenches, electric grinders, electric circularsaws, electric reciprocating saws, electric jigsaws, electric cutters,electric chain saws, electric planers, electric nail guns (includingriveting machines), electric hedge trimmers, electric lawn mowers,electric grass trimmers, electric bush cutters, electric cleaners,electric blowers, electric sprayers, electric spreaders, and electricdust collectors. Besides the electric working machines, the presentdisclosure may be applied to various jobsite electric apparatus equippedwith tools driven by power supply, for example, jobsite lightings, andjobsite audio equipment such as radios and speakers. In addition, thepresent disclosure may also be applied to other jobsite electricapparatus such as battery packs mounted with batteries, and batterychargers for the batteries. In other words, various jobsite electricapparatus may be provided with the communicating unit in the presentdisclosure and may be configured to wirelessly transmit internalinformation of the jobsite electric apparatus additionally and may beconversely configured to wirelessly receive additional information andappropriately transmit the received additional information to thejobsite electric apparatus.

(2-5) Two or more functions achieved by one element of theaforementioned embodiment may be achieved by two or more elements; orone function achieved by one element may be achieved by two or moreelements. In addition, two or more functions achieved by two or moreelements may be achieved by one element; or one function achieved by twoor more elements may be achieved by one element. Furthermore, a part ofthe configurations of the aforementioned embodiment may be omitted, andone element in any one of the embodiments may be added to or replacedwith those of other embodiment.

What is claimed is:
 1. A communicator comprising: a connector configuredto be detachably coupled to an electric working machine, the electricworking machine including: a motor; and a tool configured to be drivenby the motor; a communication circuit configured to perform wirelesscommunication; a display; a communication controller configured totransmit operational information via the communication circuit, theoperational information indicating whether the motor is being driven;and a display controller configured to show first information on thedisplay in response to the motor being driven, the first informationindicating that the motor is being driven, the display controller beingfurther configured to show second information on the display in responseto the motor being stopped, the second information indicating that themotor is stopped.
 2. The communicator according to claim 1, wherein thecommunication controller is configured to receive an operational signalindicating whether the motor is being driven, and wherein thecommunication controller is configured to transmit the operationalinformation that corresponds to the operational signal.
 3. Thecommunicator according to claim 2, wherein the communication controlleris configured to receive the operational signal from the electricworking machine via the connector.
 4. The communicator according toclaim 1, wherein the display controller is configured to receive anoperational signal indicating whether the motor is being driven, andwherein the display controller is configured to show the firstinformation or the second information on the display in accordance withthe operational signal.
 5. The communicator according to claim 4,wherein the display controller is configured to receive the operationalsignal from the electric working machine via the connector.
 6. Thecommunicator according to claim 1, wherein the communication controlleris configured to be set to an operation-transmission mode, wherein thecommunication controller in the operation-transmission mode isconfigured to transmit the operational information, and wherein thedisplay controller is configured to show the first information or thesecond information on the display in response to the communicationcontroller being set to the operation-transmission mode.
 7. Thecommunicator according to claim 6, wherein the communication controlleris further configured to be set to a registration-transmission mode,wherein the communication controller in the registration-transmissionmode is configured to transmit registration information via thecommunication circuit, the registration information including a commandto register communicator information that identifies the communicator,and wherein the display controller is configured to show thirdinformation on the display in response to the communication controllerbeing set to the registration-transmission mode, the third informationindicating that the communication controller is set to theregistration-transmission mode.
 8. The communicator according to claim7, wherein the communication controller is further configured to be setto a deletion-transmission mode, wherein the communication controller inthe deletion-transmission mode is configured to transmit deletioninformation via the communication circuit, the deletion informationincluding a command to delete the communicator information, and whereinthe display controller is configured to show fourth information on thedisplay in response to the communication controller being set to thedeletion-transmission mode, the fourth information indicating that thecommunication controller is set to the deletion-transmission mode. 9.The communicator according to claim 6, wherein the communicationcontroller is further configured to be set to a wait-transmission modein response to the connector being coupled to the electric workingmachine, wherein the communication controller in the wait-transmissionmode is configured to transmit identification information that indicatesthe communicator via the communication circuit, and wherein the displaycontroller is configured to show fifth information on the display inresponse to the communication controller being set to thewait-transmission mode, the fifth information indicating that thecommunication controller is set to the wait-transmission mode.
 10. Thecommunicator according to claim 1, wherein the display includes an LED.11. A communicator comprising: a connector configured to be detachablycoupled to a receiving side electric working machine; a communicationcircuit configured to perform wireless communication; a display; acommunication controller configured to receive operational informationvia the communication circuit, the operational information beingwirelessly transmitted from a transmission side communicator provided toa transmission side electric working machine, the operationalinformation indicating whether a motor of the transmission side electricworking machine is being driven, the communication controller beingconfigured to output the operational information to the receiving sideelectric working machine; and a display controller configured to showfirst information on the display in response to the operationalinformation indicating that the motor is being driven, the firstinformation indicating that the motor is being driven, the displaycontroller being further configured to show second information on thedisplay in response to the operational information indicating that themotor is stopped, the second information indicating that the motor isstopped.
 12. The communicator according to claim 11, wherein thecommunication controller is configured to output the operationalinformation to the receiving side electric working machine via theconnector.
 13. The communicator according to claim 11, wherein thecommunication controller is configured to be set to anoperation-receiving mode, wherein the communication controller in theoperation-receiving mode is configured to output the operationalinformation to the receiving side electric working machine, and whereinthe display controller is configured to show the first information orthe second information on the display in response to the communicationcontroller being set to the operation-receiving mode.
 14. Thecommunicator according to claim 13, wherein the transmission sidecommunicator is configured to transmit registration information, theregistration information including a command to register transmissionside communicator information that identifies the transmission sidecommunicator, wherein the communication controller is further configuredto be set to a registration-receiving mode, wherein the communicationcontroller in the registration-receiving mode is configured to registerthe transmission side communicator information received via thecommunication circuit, and wherein the display controller is configuredto show third information on the display in response to thecommunication controller being set to the registration-receiving mode,the third information indicating that the communication controller beingset to the registration-receiving mode.
 15. The communicator accordingto claim 14, wherein the transmission side communicator is configured totransmit deletion information, the deletion information including acommand to delete the transmission side communicator information,wherein the communication controller is further configured to be set toa deletion-receiving mode, wherein the communication controller in thedeletion-receiving mode is configured to delete the transmission sidecommunicator information in response to receipt of the deletioninformation via the communication circuit, and wherein the displaycontroller is configured to show fourth information on the display inresponse to the communication controller being set to thedeletion-receiving mode, the fourth information indicating that thecommunication controller is set to the deletion-receiving mode.
 16. Thecommunicator according to claim 13, wherein the communication controlleris further configured to be set to a wait-receiving mode in response tothe connector being coupled to the receiving side electric workingmachine, wherein the communication controller in the wait-receiving modeis configured to be set to the operation-receiving mode in response toreceipt of the operational information, and wherein the displaycontroller is configured to show fifth information on the display inresponse to the communication controller being set to the wait-receivingmode, the fifth information indicating that the communication controlleris set to the wait-receiving mode.
 17. The communicator according toclaim 11, wherein the display includes an LED.
 18. The communicatoraccording to claim 11, wherein the receiving side electric workingmachine includes a dust collector.
 19. An electric working machinecomprising: a first motor; a tool configured to be driven by the firstmotor; a communication circuit configured to perform wirelesscommunication; a display; a communication controller configured toreceive operational information via the communication circuit, theoperational information being wirelessly transmitted from a communicatorprovided to an additional electric working machine, the operationalinformation indicating whether a second motor of the additional electricworking machine is being driven; a motor controller configured to drivethe first motor in response to the operational information indicatingthat the second motor is being driven; and a display controllerconfigured to show first information on the display in response to theoperational information indicating that the second motor is beingdriven, the first information indicating that the second motor is beingdriven, the display controller being further configured to show secondinformation on the display in response to the operational informationindicating that the second motor is stopped, the second informationindicating that the second motor is stopped.
 20. The electric workingmachine according to claim 19, wherein the electric working machineincludes a dust collector.